{"product_id":"microppose-18mm-0-3-micron-self-adhesive-lid-filter-stickers-for-jar-lids-tissue-culture-50-pack","title":"Microppose 18mm 0.3 Micron Self-Adhesive Lid Filter Stickers for Jar Lids \u0026 Tissue Culture (50-Pack)","description":"\u003cstyle\u003e\n.mgk-pdp{--g:#1a6b3a;--g-dk:#1a3a26;--g-pale:#f6faf7;--red:#9e3b2e;--bd:#dce9e0;color:var(--g-dk);}\n.mgk-pdp p{line-height:1.65;}\n.mgk-pdp .b{font-weight:600 !important;}\n.mgk-pdp h2{color:var(--g-dk) !important;border-left:4px solid var(--g);padding-left:12px;margin:34px 0 14px;line-height:1.25;}\n.mgk-pdp ul{columns:unset !important;list-style:none;padding-left:0;margin:14px 0;}\n.mgk-pdp ul li{position:relative;padding-left:26px;margin-bottom:10px;line-height:1.55;}\n.mgk-pdp ul li::before{content:\"\";position:absolute;left:3px;top:9px;width:8px;height:8px;border-radius:50%;background:var(--g);}\n.mgk-pdp ul.mgk-check li{padding-left:28px;}\n.mgk-pdp ul.mgk-check li::before{content:\"\\2713\";background:none;color:var(--g);font-weight:700;left:0;top:0;width:auto;height:auto;border-radius:0;}\n.mgk-facts{display:flex;flex-wrap:wrap;gap:12px;margin:20px 0 6px;}\n.mgk-facts .fact{flex:1 1 140px;background:var(--g-pale);border:1px solid var(--bd);border-radius:12px;padding:14px 12px;text-align:center;}\n.mgk-facts .fact .num{display:block;font-weight:700;color:var(--g);font-size:1.15em;margin-bottom:3px;}\n.mgk-facts .fact .lbl{display:block;opacity:.75;font-size:.9em;line-height:1.3;}\n.mgk-callout{background:var(--g-pale);border-left:4px solid var(--g);border-radius:8px;padding:16px 18px;margin:18px 0;}\n.mgk-callout p{margin:0;}\n.mgk-pdp details{border:1px solid var(--bd);border-radius:12px;margin:12px 0;background:#fff;overflow:hidden;transition:border-color .2s,box-shadow .2s;}\n.mgk-pdp details[open]{border-color:var(--g);box-shadow:0 4px 14px rgba(26,107,58,.09);}\n.mgk-pdp summary.mgk-faq{list-style:none;cursor:pointer;padding:16px 54px 16px 18px;position:relative;font-weight:600;color:var(--g-dk);transition:background .2s;}\n.mgk-pdp summary.mgk-faq::-webkit-details-marker{display:none;}\n.mgk-pdp summary.mgk-faq:hover{background:var(--g-pale);}\n.mgk-pdp summary.mgk-faq::after{content:\"+\";position:absolute;right:16px;top:50%;transform:translateY(-50%);width:26px;height:26px;line-height:25px;text-align:center;border-radius:50%;background:var(--g);color:#fff !important;font-weight:400;font-size:1.25em;transition:transform .25s;}\n.mgk-pdp details[open] summary.mgk-faq::after{transform:translateY(-50%) rotate(45deg);}\n.mgk-pdp .faq-body{padding:2px 18px 18px;animation:mgkFade .25s ease;}\n.mgk-pdp .faq-body p{margin:0;line-height:1.6;}\n@keyframes mgkFade{from{opacity:0;transform:translateY(-4px);}to{opacity:1;transform:none;}}\n.mgk-cta-card{background:var(--g-pale);border:1px solid var(--bd);border-radius:16px;padding:22px 24px;text-align:center;margin-top:14px;}\n.mgk-btn{display:inline-block;background:var(--g);color:#fff !important;text-decoration:none;font-weight:600;padding:12px 28px;border-radius:999px;transition:background .2s,transform .15s;margin-top:14px;}\n.mgk-btn:hover{background:var(--g-dk);transform:translateY(-1px);}\n\u003c\/style\u003e\n\n\u003cdiv class=\"mgk-pdp\"\u003e\n\n\u003cp\u003eTurn any jar lid or culture container into a breathable, contamination-proof workspace in seconds. The \u003cspan class=\"b\"\u003eMicroppose 18mm 0.3 Micron Self-Adhesive Lid Filter Stickers\u003c\/span\u003e peel and stick directly over a drilled hole in metal or plastic lids, letting your culture breathe while blocking airborne spores and bacteria.\u003c\/p\u003e\n\n\u003cp\u003eBacked by industrial-strength \u003cspan class=\"b\"\u003e3M adhesive\u003c\/span\u003e, these filters stay put through handling, autoclaving, and long incubation runs — no peeling, no falling off. Each sheet gives you \u003cspan class=\"b\"\u003e50 filters\u003c\/span\u003e, making them the fastest, most economical way to build your own sterile lids for injections and transfers. The compact 18mm size is perfect for grain spawn jars, liquid culture jars, and small tissue culture vessels.\u003c\/p\u003e\n\n\u003cdiv class=\"mgk-facts\"\u003e\n  \u003cdiv class=\"fact\"\u003e\n\u003cspan class=\"num\"\u003e0.3µm\u003c\/span\u003e\u003cspan class=\"lbl\"\u003eFiltration Efficiency\u003c\/span\u003e\n\u003c\/div\u003e\n  \u003cdiv class=\"fact\"\u003e\n\u003cspan class=\"num\"\u003e3M\u003c\/span\u003e\u003cspan class=\"lbl\"\u003eAdhesive Backing\u003c\/span\u003e\n\u003c\/div\u003e\n  \u003cdiv class=\"fact\"\u003e\n\u003cspan class=\"num\"\u003e50\u003c\/span\u003e\u003cspan class=\"lbl\"\u003eFilters Per Sheet\u003c\/span\u003e\n\u003c\/div\u003e\n  \u003cdiv class=\"fact\"\u003e\n\u003cspan class=\"num\"\u003e18mm\u003c\/span\u003e\u003cspan class=\"lbl\"\u003eRound\u003c\/span\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eWhy Growers Choose These Filters\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cspan class=\"b\"\u003eTrue 0.3 Micron Filtration\u003c\/span\u003e – Stops contaminant spores and bacteria while allowing clean, consistent gas exchange.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cspan class=\"b\"\u003eWon't Fall Off\u003c\/span\u003e – Industrial 3M adhesive holds through autoclaving, humidity, and months of incubation.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cspan class=\"b\"\u003eLightning-Fast Application\u003c\/span\u003e – Peel and stick in seconds; no cutting, taping, or polyfill stuffing.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cspan class=\"b\"\u003eBreathes Better\u003c\/span\u003e – A proprietary micron layer resists moisture saturation for faster, cleaner colonization.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eHow to Apply\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eDrill or punch a hole in your jar lid or tissue culture lid (a 1\/4\" hole works well for 18mm; add a second hole for extra airflow).\u003c\/li\u003e\n  \u003cli\u003ePeel a filter from the sheet and press it firmly over the opening, centering it so the adhesive fully seals around the hole.\u003c\/li\u003e\n  \u003cli\u003ePair with a \u003cspan class=\"b\"\u003eself-healing injection port\u003c\/span\u003e for a complete DIY sterile lid ready for inoculation and transfers.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cul class=\"mgk-check\"\u003e\n  \u003cli\u003e\n\u003cspan class=\"b\"\u003e0.3 micron filtration efficiency\u003c\/span\u003e – blocks spores and bacteria, allows clean airflow\u003c\/li\u003e\n  \u003cli\u003e\n\u003cspan class=\"b\"\u003eStrong 3M adhesive backing\u003c\/span\u003e – stays put even after autoclaving\u003c\/li\u003e\n  \u003cli\u003e\n\u003cspan class=\"b\"\u003eHydrophobic \u0026amp; oleophobic\u003c\/span\u003e – resists moisture saturation and oil\u003c\/li\u003e\n  \u003cli\u003e\n\u003cspan class=\"b\"\u003eFully autoclavable\u003c\/span\u003e – high-temperature resistant for repeated sterilization\u003c\/li\u003e\n  \u003cli\u003e\u003cspan class=\"b\"\u003eMade from 100% recycled material\u003c\/span\u003e\u003c\/li\u003e\n  \u003cli\u003e\n\u003cspan class=\"b\"\u003e50 filters per sheet\u003c\/span\u003e – 18mm round\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eCommon Uses\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eGrain spawn jars and liquid culture jars\u003c\/li\u003e\n  \u003cli\u003eAgar work and spore-to-liquid culture\u003c\/li\u003e\n  \u003cli\u003ePlant tissue culture vessels and containers\u003c\/li\u003e\n  \u003cli\u003eDIY sterile lids for injections and transfers\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cdiv class=\"mgk-callout\"\u003e\n\u003cp\u003eUnlike the re-purposed filters sold everywhere else, these use a \u003cspan class=\"b\"\u003eunique proprietary micron layer\u003c\/span\u003e that does not break down from steam, resists moisture saturation, and breathes far better than cheaper alternatives — giving you faster, cleaner colonization every time.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\n\u003cdetails\u003e\n  \u003csummary class=\"mgk-faq\"\u003eWhat size hole should I drill for these filters?\u003c\/summary\u003e\n  \u003cdiv class=\"faq-body\"\u003e\u003cp\u003eDrill or punch a hole smaller than the filter so the 3M adhesive fully seals around the edge. For the 18mm size, a 1\/4\" hole works well, and you can add a second small hole for extra gas exchange on grain jars.\u003c\/p\u003e\u003c\/div\u003e\n\u003c\/details\u003e\n\n\u003cdetails\u003e\n  \u003csummary class=\"mgk-faq\"\u003eCan these be autoclaved or pressure cooked?\u003c\/summary\u003e\n  \u003cdiv class=\"faq-body\"\u003e\u003cp\u003eYes. They are fully autoclavable and high-temperature resistant. The 3M adhesive and proprietary micron layer hold up to repeated steam sterilization without peeling or breaking down.\u003c\/p\u003e\u003c\/div\u003e\n\u003c\/details\u003e\n\n\u003cdetails\u003e\n  \u003csummary class=\"mgk-faq\"\u003eWhat can I use them for?\u003c\/summary\u003e\n  \u003cdiv class=\"faq-body\"\u003e\u003cp\u003eGrain spawn jars, liquid culture, agar work, and plant tissue culture vessels — anywhere you need sterile gas exchange. Pair them with a self-healing injection port to build a complete DIY sterile lid for inoculation and transfers.\u003c\/p\u003e\u003c\/div\u003e\n\u003c\/details\u003e\n\n\u003cdetails\u003e\n  \u003csummary class=\"mgk-faq\"\u003eHow is 0.3 micron different from cheaper filter discs?\u003c\/summary\u003e\n  \u003cdiv class=\"faq-body\"\u003e\u003cp\u003eThe 0.3 micron layer blocks bacteria and mold spores while still breathing well. Unlike re-purposed filters, this proprietary layer resists moisture saturation and does not degrade from steam, so you get more reliable, faster colonization.\u003c\/p\u003e\u003c\/div\u003e\n\u003c\/details\u003e\n\n\u003cdetails\u003e\n  \u003csummary class=\"mgk-faq\"\u003eShould I get the 18mm or the 28mm?\u003c\/summary\u003e\n  \u003cdiv class=\"faq-body\"\u003e\u003cp\u003eThe 18mm (50 per sheet) is ideal for standard grain spawn jars, liquid culture jars, and small tissue culture containers. Choose the 28mm (21 per sheet) if you want more filter surface area for larger lids, wide-mouth jars, or tubs where extra gas exchange helps.\u003c\/p\u003e\u003c\/div\u003e\n\u003c\/details\u003e\n\n\u003ch2\u003eComplete Your Sterile Lid\u003c\/h2\u003e\n\u003cdiv class=\"mgk-cta-card\"\u003e\n\u003cp\u003ePair these filters with a \u003cspan class=\"b\"\u003eself-healing injection port\u003c\/span\u003e to build a reusable DIY sterile lid you can inoculate again and again without contamination.\u003c\/p\u003e\n\u003ca class=\"mgk-btn\" href=\"https:\/\/www.midwestgrowkits.com\/collections\/lid-filters-injection-ports\" target=\"_blank\"\u003eShop Injection Ports \u0026amp; Lid Filters\u003c\/a\u003e\n\u003c\/div\u003e\n\n\u003c\/div\u003e\n\n\u003cscript type=\"application\/ld+json\"\u003e\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@type\": \"FAQPage\",\n  \"mainEntity\": [\n    {\"@type\": \"Question\", \"name\": \"What size hole should I drill for these filters?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Drill or punch a hole smaller than the filter so the 3M adhesive fully seals around the edge. For the 18mm size, a 1\/4 inch hole works well, and you can add a second small hole for extra gas exchange on grain jars.\"}},\n    {\"@type\": \"Question\", \"name\": \"Can these be autoclaved or pressure cooked?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Yes. They are fully autoclavable and high-temperature resistant. The 3M adhesive and proprietary micron layer hold up to repeated steam sterilization without peeling or breaking down.\"}},\n    {\"@type\": \"Question\", \"name\": \"What can I use them for?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Grain spawn jars, liquid culture, agar work, and plant tissue culture vessels, anywhere you need sterile gas exchange. Pair them with a self-healing injection port to build a complete DIY sterile lid for inoculation and transfers.\"}},\n    {\"@type\": \"Question\", \"name\": \"How is 0.3 micron different from cheaper filter discs?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"The 0.3 micron layer blocks bacteria and mold spores while still breathing well. Unlike re-purposed filters, this proprietary layer resists moisture saturation and does not degrade from steam, so you get more reliable, faster colonization.\"}},\n    {\"@type\": \"Question\", \"name\": \"Should I get the 18mm or the 28mm?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"The 18mm (50 per sheet) is ideal for standard grain spawn jars, liquid culture jars, and small tissue culture containers. Choose the 28mm (21 per sheet) if you want more filter surface area for larger lids, wide-mouth jars, or tubs where extra gas exchange helps.\"}}\n  ]\n}\n\u003c\/script\u003e","brand":"Microppose","offers":[{"title":"Default","offer_id":47619153166485,"sku":"MFS18","price":7.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0712\/0679\/7461\/files\/Microppose_18mm_lid_filters.jpg?v=1784894206","url":"https:\/\/www.midwestgrowkits.com\/products\/microppose-18mm-0-3-micron-self-adhesive-lid-filter-stickers-for-jar-lids-tissue-culture-50-pack","provider":"Midwest Grow Kits","version":"1.0","type":"link"}